W83627DHG Datasheet, PDF (40/268 Pages) Winbond – WINBOND LPC I/O

W83627DHG
7. HARDWARE MONITOR
7.1 General Description
The W83627DHG monitors several critical parameters in PC hardware, including power supply
voltages, fan speeds, and temperatures, all of which are very important for a high-end computer system
to work stably and properly.
The W83627DHG can simultaneously monitor all of the following inputs:
• Nine analog voltage inputs (four intrinsic monitor VBAT, 3VSB, 3VCC and AVCC power; five
externally monitored power)
• Five fan tachometer inputs
• Three remote temperatures, by thermistor or from the CPU thermal-diode output(voltage or
Current Mode)
• One case-open detection signal.
These inputs are converted to digital values using a built-in, eight-bit analog-to-digital converter (ADC).
In response to these inputs, the W83627DHG can generate the following outputs:
• Four PWM (pulse width modulation) or DC fan outputs for the fan speed control
• Beep tone output for warnings
• SMI#
• OVT# signals for system protection events
The W83627DHG provides hardware access to all monitored parameters through the LPC or I²C
interface and software access through application software, such as Winbond’s Hardware Doctor^TM, or
BIOS. In addition, the W83627DHG can generate pop-up warnings or beep tones when a parameter
goes outside of a user-specified range.
The rest of this section introduces the various features of the W83627DHG hardware-monitor capability.
These features are divided into the following sections:
• Access Interfaces
• Analog Inputs
• Fan Speed Measurement and Control
• Smart Fan Control
• SMI# interrupt mode
• OVT# interrupt mode
• Registers and Value RAM
7.2 Access Interfaces
The W83627DHG provides two interfaces, LPC and I²C, for the microprocessor to read or write the
internal registers of the hardware monitor.
Publication Release Date: Aug, 22, 2007
-28-
Version 1.4